Let x represent the number of liters of 50% acid Theresa puts into the mix. The the number of liters of 30% acid will be (420-x). The total amount of acid in the final solution will be ...
0.50x + 0.30(420-x) = 0.45(420)
0.20x + 126 = 189 . . . . . . . . . . . . . . . simplify
0.20x = 63 . . . . . . . . . . . . . . . . . . . . . subtract 126
x = 63/0.20 = 315 . . . . . . . . . . . . . . . liters of 50% solution
(420-x) = 420-315 = 105 . . . . . . . . . liters of 30% solution
Theresa should mix ...
105 liters of 30% solution
315 liters of 50% solution
There u just needed to search the formula
1/2 over -2/5 + (-1/4)
10/20 over -8/20 + (-5/20)
1 5/20 + (-5/20)
1
The answer is 1
0/2=0 because anything divided by zero is zero.
9514 1404 393
Answer:
C f(x) = {4e^x -5, ..., -x +7, ...
Step-by-step explanation:
The easiest portion to check is the constant section in the interval [0, 6]. All of the function definitions agree on that, so that doesn't help choose the right answer.
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Next easiest is the linear section at the right. It has a negative slope. Extension of the line to the y-axis shows it has a positive y-intercept. This eliminates choices A and D.
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The horizontal asymptote of the exponential portion at the left is -5. Both of the remaining choices B and C agree on that. The exponential is increasing at an increasing rate, so its coefficient is positive. This eliminates choice B.
The appropriate description of the function on the graph is offered by choice C.
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The graph below plots the function. We note that the given graph seems to show the exponential curve incorrectly.